The traditional internal combustion engine relies on connecting rods for transmitting combustion power from a piston main body to a crankshaft of the engine, thereby converting the linear motion of the piston main body to rotational motion at the crankshaft. Combustion power is generated from the intermittent ignition of gasoline that is injected into the combustion chamber, which creates extreme pressures that are applied to the piston and connecting rod. In particular, the interface between the piston pin bore of the connecting rod and the piston pin experiences continuous radial loads during operation, where only a limited amount of a lubricant may be available for lubricating the interface. In an effort to enhance lubrication at the interface of the piston pin and the connecting rod bore, lubrication jets may be directed from the engine crankcase toward the piston pin interface.
Typically, lubrication jets are directed toward the piston to cool it. Known lubrication jets are typically mounted on the crankshaft pin or the crankshaft end of the connecting rod, and therefore can only provide lubrication at certain times during the combustion cycle such as when the connecting rod is positioned such that the jet is aimed toward the piston pin. Additionally, lubrication pressure may be inconsistent, especially upon during cold start conditions when oil pressure may be at a minimum. As a result, lubrication of the piston pin and connecting rod interface, as well as cooling provided to the interface between the piston pin and the connecting rod, may be undesirably intermittent and incomplete.
Accordingly, there is a need for a connecting rod providing improved lubrication to the piston pin interface.